森林伐採・管理がもたらす温暖化効果の評価

森林砍伐和管理造成的全球变暖影响评估

• 批准号: 15710031
• 负责人: 篭谷 泰行
• 金额: $ 2.43万
• 依托单位: The University of Shiga Prefecture
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Young Scientists (B)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15710031/
• 关键词: 森林伐採; 林地処理; 地球温暖化; 温室効果ガス; 土壌; 林地管理

森林伐採とその後の異なる林地処理がもたらす温暖化効果を評価するため、滋賀県高島市の落葉広葉樹二次林調査地において実験を継続した。斜面に10m×30mの区画を全部で17区画設置し、それぞれの区画に(1)伐採後植生の再生を排除し、さらに寒冷紗をかけて温度の上昇を抑制する、(2)伐採後植生の再生を排除するのみ、(3)伐採後植生を積極的に導入する、(4)非伐採(対照)、(5)その他(伐採後人為的に表土攪乱を行う場合と伐採後従来施業どおりスギ植樹する場合)の処理を、(1)〜(4)は3区画ずつ、(5)は1区画ずつ適用した。非伐採区での地上部植生の成長量は2.3t/ha/yrであった。土壌のガス代謝(温室効果ガスCO_2、CH_4、N_2Oの放出・吸収速度)測定の結果、CO_2放出速度は伐採後減少し、N_2O放出速度は逆に増大の傾向が見られた。CH_4吸収速度は土壌攪乱によりやや減少の傾向が見られたほかは顕著な変化は認められなかった。各区画の比較から、CO_2放出速度の伐採にともなう変化の内訳は、植生が除かれることによる変化が-29%、土壌温度の上昇にともなう変化が+24%、表土攪乱による変化が-14%となった。地上部植生、土壌のガス代謝の変化の測定結果にもとづき、この調査地の森林伐採にともなう温暖化効果を評価した。伐採により、地上部植生の純生産量分である11.5t CO_2/ha/yrが失われた。土壌呼吸量は1.5t CO_2/ha/yr放出量が減少した。土壌のCH_4吸収量はCO_2換算で0.01t CO_2/ha/yr減少した。N_2O放出量は同じくCO_2換算で0.3t CO_2/ha/yr増加した。結局、合計で10.3t CO_2/ha/yrの温暖化効果と推定された。この内訳をガスごとに見ると、CO_2、CH_4、N_2Oがそれぞれ97.1、0.1、2.9%となり、伐採にともなう地上部植生のCO_2固定機能の消失が圧倒的に大きく働くことが示された。ただし、土壌のガス代謝の変化だけで見るとまた大きく異なることも明らかとなった。

After the felling of the forest, the forest land was cut, and the forest land was warmed up and warmed up. The results showed that the forest land in Gaoyang city was damaged and the secondary forest was damaged. All the pictures in the slope area of 10m × 30m are set up in area 17, and the pictures in the area are as follows: (1) the exclusion of plant regeneration after felling, the suppression of plant regeneration after cutting, the inhibition of plant regeneration after cutting, (2) the exclusion of plant regeneration after felling, (3) the active treatment of plant regeneration after felling, (4) non-logging (license), (5) to treat him (after felling for artificial topsoil disorderly treatment and after felling) to carry out the operation of mining and planting plants in areas 3, (1) ~ (4), and (5) to draw and use pictures in area 1. The growth of aboveground plants in the non-felling area is 2.3t/ha/yr growth. The emission rate of CO_2, CH_4 and N2O in greenhouse was measured, the emission rate of CO_2 decreased after cutting, and the emission rate of N2O increased in the opposite direction. The CH_4 absorbs the speed, the soil is in disorder, the soil is in disorder, and the speed is low. In each area, the release rate of CO_2 is less than 29%, the temperature of soil is increased by 24%, and the topsoil is disorderly by 14%. The results of the measurement of aboveground plants, soil plants and soil samples showed that there were no changes in forest felling and warming in the land. The biomass of felling and aboveground plants is 11.5t CO_2/ha/yr. Soil respiration volume 1.5 t CO_2/ha/yr release volume less than normal. The amount of CH_4 absorbed by soil is 0.01t CO_2/ha/yr less than that of CO_2. The amount of N2O emission is the same as that of N2O emission CO_2, which is calculated to be 0.3t CO_2/ha/yr plus N2O. At the end of the day, the warming effect of 10.3t CO_2/ha/yr was presumed to be significant. For example, CO_2, CH_4, CH_4, N2O, and so on, please see the indication that the CO_2 fixed machine can be used in the upper part of the plant. In the first place, there is no need to know what is going on in the world.